Morphofunctional changes of the skin on the background of the introduction of exogenous pigment

The widespread popularity of tattoos in modern society raises the question of their long-term effects on the human body. Despite the centuries-old history of this practice, the fundamental aspects of the interaction of complex chemical compositions injected into the skin with living tissues remain an area of active scientific discussion. This study aims at a comprehensive analysis of existing scientific data concerning the structural and functional transformations of the skin induced by the permanent presence of foreign color agents. The methodological basis of the work was a systematic review in accordance with the principles of PRISMA. The selection of relevant sources was carried out in international and Russian bibliographic databases with an emphasis on generalizing works – systematic reviews and meta-analyses. This made it possible to analyze the consolidated conclusions of many primary studies and identify universal patterns. The results of the analysis demonstrate that tattoo pigments are not biologically inert. Their administration initiates a complex and prolonged immune response. After a short-term acute reaction, chronic inflammation develops, the morphological substrate of which is persistent lymphohistiocytic infiltration of the dermis. The key cellular element is macrophages, phagocytic pigment particles and forming long-lived cell pools. In some cases, this process takes the form of granulomatous inflammation or leads to severe reactive hyperplasia of the epidermis, which can mimic a malignant neoplasm during histological examination. Special attention is paid to the role of the chemical composition of pigments in provoking specific pathologies. It has been established that certain colors, in particular red, are statistically significantly associated with the development of both benign and malignant proliferative processes. In addition, the risks associated with the destruction of pigments in vivo, including laser tattoo removal, are considered, during which potentially toxic and carcinogenic decay products can form and systemically spread. In conclusion, it is emphasized that tattooing creates a unique and persistent pathological background in the skin, characterized by chronic inflammation and the constant presence of foreign material. This condition requires increased oncological alertness on the part of clinicians and pathologists, as well as the development of strategies for long-term patient monitoring. The data obtained indicate the urgent need for further in-depth and standardized studies for a comprehensive assessment of the long-term risks associated with permanent cosmetic skin coloring.